F
FLUORINE
(L. and F. fluere, flow, or flux)
F at. wt. 18.9984
at. no. 9
f.p. -219.627°C (1 atm.)
b.p. - 188.14°C
density 1.696 g/l (0°C, 1 atm.)
sp. gr. of liquid 1.108 at b.p.
valence 1.
Electronic configuration
| SHELL |
K |
L |
M |
N |
O |
P |
Q |
| SUB SHELL |
He |
Neon |
Argon |
Krypton |
Xenon |
Radon |
Eka-radon |
| 1s |
2s 2p |
3s 3p |
3d 4s 4p |
4d 5s 5p |
4f 5d 6s 6p |
5f 6d 7s 7p |
| Fluorine
|
1s22s22p5 |
|
|
|
|
|
| Symbol
|
2P3/2 |
Fluorine. In 1529, Georgius Agricola des-
cribed the use of fluorspar as a flux; and as early as 1670
Schwandhard found that glass was etched when exposed -to
fluorspar treated with acid. Scheele and many later jn-
vestigators, including Davy, - Gay-Lussac, Lavoisier, and
Thenard, experimented with hydrofluoric acid, some experi-
ments endhig in tragedy. The element was finally isolated in
1886 by Moisson after nearly 74 years of continuous effort.
Fluorine occurs chiefly in fluorspar (CaF2) and cryolite
(Na2AlF6), but is rather widely distributed in other minerals.
It is a member of the halogen famfly of elements, and
obtained by electrolyzing a solution of potassium hydrogen
fluoride in anhydrous hydrogen fluoride in-a vessel of metal
or transparent quprspar. Modern commercial production
methods are essentially variations on the. procedures first
used by Moisson. Fluorine is the most electronegative and
reactive of all elements. It is a pale yellow, corrosive gas,
which reacts with practically all organic and inorganic sub-.
stances. Finely divided metals, glass, ceramics, carbon, and
even water burn in fluorine with. a bright flame, Until
World War II, there was no commercial production, of
elemental fluorine. The atom-bomh project and nuclear
energy applications, however, made it necessary to produce
large quantities. Safe handling techniques have now Ieeen
developed and it is possible at present to transport liquid
fluorine by the ton. Fluorine and its compounds are used in
producing uranium (from the hexafluoride) and more than
100 commercial fluorochemicals, including many well-known
high-temperature plastics. Hydrofluoric acid is extensively
used for etching the glass of light bulbs, etc. Fluorochloro
hydrocarbons are extensively 'used in air conditioning and
refrigeration. It has been suggested that fluorine can be su~
stituted for hydrogen - whetever it occurs in organic -com-
pounds, which - could lead to an astronomical number of
new fluorine compounds. The presence of fluorine as a
soluble fluoride in drinking water to the extent of 2 ppm
may cause mottled enamel in teeth, when. used by children
acquiring permanent teeth; in smaller amounts, however,
fluorides are said to be beneficial and used in water supplies
to prevent dental cavities. Elemental fluorine is being studied'
as a rocket propellant as it has an exceptionally high s-ic
impulse value. Compounds of fluorine with rare gases have
now been confirmed. Fluorides of xenon, radon, and kryp-
ton are among those reported. Elemental fluorine and the
fluoride ion are highly toxic. The free element has a charac-
teristic pungent odor, detectable in concentrations as low
as 20 parts per billion, which is below the safe working
level. The recommended maximum allowable concentration
for a daily 8-hr. exposure is 0.1 ppm.
© 1999 F. Davies
Delphi O.E.M. Co.
All rights reserved
